Topical anesthetic

Abstract

A topical anesthetic is provided containing about 3 wt % to 10 wt % tetracaine in a vehicle suitable for administration to the skin or mucosa. The vehicle for transporting the tetracaine includes a water soluble mucoadhesive or a combination of mucoadhesives such as a high molecular weight poly(ethylene oxide) homopolymer and a cellulose polymer. The vehicle also includes propylene glycol. The tetracaine is ground into a powder and is suspended in a plasticized hydrocarbon gel which completes the vehicle.

What is claimed: 
     
       1. A topical anesthetic for use in producing local anesthesia in about three to five minutes when applied to the skin or mucosa, said topical anesthetic comprising tetracaine free base in a non-aqueous vehicle, wherein the non-aqueous vehicle comprises a high molecular weight poly(ethylene oxide) homopolymer in combination with a cellulose polymer wherein the combination makes up about 10 wt % of the topical anesthetic, said high molecular weight poly(ethylene oxide) homopolymer is present in an amount from about 3 wt % to about 8 wt % of the combination; propylene glycol in an amount from about 5 wt % to 15 wt % of the topical anesthetic; and a plasticized hydrocarbon gel in an amount of about 70 wt % of the topical anesthetic, said topical anesthetic being stable under refrigeration for at least twenty-five months as to efficacy and potency of the tetracaine free base as an anesthetic. 
     
     
       2. The topical anesthetic of  claim 1  wherein the poly(ethylene oxide) homopolymer has a molecular weight about 4,000,000 daltons. 
     
     
       3. The topical anesthetic of  claim 1  wherein the poly(ethylene oxide) is present in an amount of about 5 wt % and the cellulose polymer is sodium carboxymethylcellulose and is present in an amount of about 4 wt % of the combination. 
     
     
       4. The topical anesthetic of  claim 3  wherein the propylene glycol is present in an amount of about 3 wt % to about 10 wt %. 
     
     
       5. The topical anesthetic of  claim 4  having a consistency of a paste and an anesthetic duration of about one to one and one-half hours.